Apparatus for oxidizing or roasting refractory ores.



Patented Mar. 20, |900.

APPARATUS FDR DXIDIZING 0B RUASTING BEFRACTORY DRES..

(Application md 1m. 15. 1e99.|

(No Model.)

. r Illlhll Tourne., WASHINGTON n c NETED 5ST 1q -TES PATENT freres.

ROBERT A. STEWART, OF KANSAS CITY, MISSOURI, ASSIGNOR TO THE STEWARTOXIDIZING COMPANY, OF COLORADO;

APPAR/iiils' FOR oxmlzme 0R RoAsnNc REFRACTORY GRES.'

SPECIFICATION forming part of Letters Patent No. 645,761, dated March20, 19O. Application filed December 15, 1899. Serial No. 740,394. (Nomodel.)

T0 all whom, zit' may concern.-

Be it known that I, ROBERT A. STEWART, a citizen of the United States,residing at Kansas City, in the county of Jackson and State of Missouri,have invented anew and useful Apparatus for Oxidizing or RoastingRefractory Ores, of which the following is a specilication.

My invention relates to apparatus for converting refractory intofree-milling ore; and it consists in certain novel and peculiar featuresof construction and combinations of parts, as hereinafter described andclaimed.

To the principle on which my invention is based, and, in factto theelements constituting the apparatus@ make' no claim, except as regardstheir peculiarity of construction and' arrangement and the advantageswhich such peculiarities impart in the reduction of refrac tory tofree-milling ore.

One object, therefore, of myinvention is to produce apparatus wherebythe process of charging the apparatus with refractoryV ore andtransforming such ore into free-milling ore and then discharging thelatter into a convenient receptacle may be rendered more expeditious,and therefore economical, than has been possible heretofore; and afurther obJ ect is to provide a construction whereby an am-v ple supplyof oxygen is introduced within the ore-cylinder to not only supportcombustion, but also to thoroughly and effectively oxidize the contentsof the cylinder.

' A still further object is to produce an apparatus which is of simple,strong, and durable construction.

In order that the invention may be fully un-r derstood, reference is tobe had to the accompanying drawings, in Which- Figure 1 represents aview, partly in vertical section and partly in side elevation, of anapparatus embodying my invention. Fig. 2 is an enlarged cross-section ofthe cylinderneck. Fig. 3 is a vertical longitudinal section of thecylinder-neck. Fig. 4 is a face view of part of the hinged door at therear end of the cylinder, the same being illustrated on the same scaleas Fig. 2. Fig. 5 is a view of the rear end of the cylinder. Fig. 6 is avertical central section of the rear end of the cylinder. Fig. 7 is asection illustrating the means for securing the manhole-covers inposition.

Referring to the drawings in detail, 1 designates a brick or other solidfoundation, and 2 a set of bearing-standards erected thereon. 3designates a shaft jou-rnaled in each longitudinally alined pair ofstandards, and 4 flanged guide or supporting rollers journaled on saidshafts within said standards.. In practice there are four of thesestandards,arranged rectangularly with relation to each other, and inconsequence two shafts and four rollers, in order to form a reliablesupport for the cylinder hereinafter described; but as this cylinder-supportin g mechanism is not claimed as new it is shown only in sideelevation, and as a result one pair of standards, one setvof rollers,and one shaft only appear. Rigidly mounted on one of said shafts outwardof its rollers 4 are the cog-pinions 5, and upon one end of the sameshaft by preference is secured a worm'wheel 6.

7 designates one or more bearings erected on the foundation 1, and 8 aworm-shaft journaled therein and meshing with the wormwheel 6, wheel 9being belted or otherwise geared to a suitable motor for operating said.worm-shaft and the parts in gear therewith,

as will hereinafter appear.

10 designatesa large oxidizing or roasting cylinder lined withfire-brick or equivalent material in the customary manner, and 11 a pairof bands shrunk or otherwise rigidly secured upon the cylinder andengaged by the flanged rollers 4 at opposite sides of and equaldistances from the axis of the cylinder, the flanges of said wheelsbearing against the inner edges of said bands to prevent anylongitudinal movement or creepage of the cylinder.

l2designates large cog-rims secured rigidly upon the cylinder near itsends and meshing continuously with the cog-pinions 5, the latter thusserving to impart a slow rotating movement to the cylinder.

At suitable distances apart the cylinder is provided with the manholes13 and at oppo` site ends of the same with the lugs 14 and 15. Hooks 16are pivoted to the lugs 15 and when the cylinder is in operation areengaged by the free ends of the bridge-bars 17, pivoted,

IOO

as at 18, to the lugs 14. 19 designates clamping-screws extendingoperatively through the center of said bars and having their enlargedinner ends swiveled in the circular cavities 21, formed in the faces ofthe manhole-covers 20, the connection between the clampingscrews andsaid covers being made permanent by means of the plates 22, embracingthe screws outward of their enlarged ends and secured rigidly to thecovers.

lVhen necessary to discharge the contents of the cylinder, the motion ofthe latter is arrested when the manholes are vertical with its axis. Theoperator in charge then turns the clamping-screws in the properdirection to move the bridge-bar 17 inward until the pivoted hook 16 canbe thrown out of engagement therewith. As soon as this .is accomplishedthe weight of the cover is sufficient to cause it to swing down with thebridge-bar to a vertically-pendent position and permit the greater partof the contents of the cylinderto escape through the manholes into asuitable receptacle placed to receive it. In this connection it may bestated that two manholes are employed in order to facilitate theoperation of discharging the oxidized ore from the cylinder and ofrecharging the latter with refractory ore, this recharging of coursetaking place when the uncovered manholes are above the axis of thecylinder. The operation of securing the covers in position is thereverse of that above describedthat is to say, the hook 16 is pushed toone side to permit the cover carried by the pivoted bridgebar to bepositioned in the hole, and then said hook is caused to overlap the freeend of the bridge-bar 17 and the screw 19 turned in the oppositedirection. The tendency of the screw to move forward is of courseresisted as soon as the cover is seated tightly in the hole, and as themanipulation of the screw continues the bridge-bar is moved outwarduntil it is clamped with great power against the said hook, the engagingsurface of the bar and the lug being inclined, (see Fig. 5,) in orderthat there may be no possible chance of accidental disengagement whenonce properly secured together.

The rear end of the cylinder consists, in the main, of a door 23, whichis hinged, as at 24, and is provided with a discharge-opening surroundedby a circular neck 25, lined with rebrick 26, like the body of thecylinder, and vertically below said discharge-opening the door isprovided with a notch 27, formed by and between the segmentalcam-shoulders 28, cast with or secured to the door. The door is adaptedto be locked reliably in its closed position by means of the lever 29,pivoted to the lug 30 of the cylinder and adapted to be forced upwardover one inclined shoulder 28 or the other until it registers with andsnaps back into the notch 27, thuslocking the door reliably closed. Toopen the door, the lever is grasped and sprung outward slightly and thenswung pivotally toward one side or the other, as shown in Fig. 5. Afterthe door is unlocked it may be swung open and maintained in suchposition by a pulley and tackle (not shown) or any other suitable meansin order that the operator may dislodge and discharge the remainingcontents of the cylinder through either of the manhole-openings or saiddoor-opening.

To make it possible to open the cylinderdoor, I provide a stack 31,preferably of brick and inclosed in a suitable metallic frame 32 to holdit intact. This frame is provided with depending bearings 33, in whichare journaled flanged wheels 34, mounted upon the track-rails 35,extending at right angles to the cylinder and secured upon thefoundation 1 in any suitable manner. The stack also comprises thestationary sleeve 36 and the sliding sleeve 37, the latter at one endeX- ternally embracing the sleeve 25 of the cylinder and projecting intosleeve 36 at the other, and in order that it may be convenientlyadjusted it is provided with one or more handles 38.

39 designates a stationary sleeve projecting upward from and formingpart of the stack, and 40 a sliding sleeve mounted thereon, providedwith a handle or handles 41. The upper endof the sleeve 40 projects intothe stationary pipe 42, extending down through the supporting-platform43 and provided With an angle-band 44, resting upon said platform.

When it is desired to obtain access to the cylinder through thedoor-opening in its end, the operator grasps handle 41 and slides sleeve40 down upon sleeve 39 until the former is entirely disengaged from thestationary pipe 42.` He then grasps handle 38 and slides sleeve 37outward until it is entirely disengaged from sleeve 25. The stack maynow be rolled along the track until the door is free to open to itswidest extent. The reverse of the operation just described reassemblesthe stack in its proper relation to the cylinder, as will be readilyunderstood.

45 designates a furnace erected at the front end of the cylinder anddivided by the customary grate 46 into an upper or combustion chamberand the lower chamber or ash-pit, entrance to the former beingcontrolled by a door 47 and to the latter by a door 48. At the rear endof the combustion-chamber is an opening 49, (shown only in Fig. 1,) inwhich is secured the cylinder 50, said cylinder forming a neck for andabout which the roastingcylinder 10 rotates, as shown in Fig. 3, saidcylindrical neck being also lined with Iirebrick, as shown at 5l, andprovided with two sets of radial pipes 52 and 53, extending through thewall of the neck and communieating at their outer ends with' the annularchamber 54, said chamber being centrally partitioned to provide thesteam-chamber 55 and the air-chamber 56, the former being connected tothe valve-controlled steam-supply pipe 57 and the latter to thevalve-controlled IOC IIO

air-supply pipe 58, through which pipes steam and air under pressure areadapted to be discharged radially into the cylinder for a purpose whichis hereinafter explained.

59 designates a valve-controlled steam-pipe projecting into thecombustion-chamber of the furnace and arranged to discharge a steam-jetaxially through the neck-passage and into the roasting-cylinder, thispipe being protected by the inclosing fire-brick pipe 60 and theinterposed lining 6l, of asbestos. The steam from said pipe passingthrough and overthe re is superheated and decomposed by the union of itsoxygen with the carbon from the gases of th'e furnace, thus increasingthe efficiency of the latter. The force of the jet, with the assistanceof an air-blast discharged from the pipe 62 down upon the bottom of theash-pit, as indicated in Fig. 1, creates a forced draft through thefurnace and the roasting-cylinder; The particular effect of this forcedblast on the steam and air discharged into the neck-passage for thepurpose of providing an ample supply of oxygen is to impart a rolling orspiral motion to the same, Which tends to facilitate its expansion andaccelerate the equalization of the heat, and as the. discharge-passageis smaller than the supply-passage creates a pressure, which completesthe expansion of this steam and air, and consequently imparts an equaldegree of heat to the entire contents of the cylinder, which at thistime is slowly revolving in order to gradually expose every particle ofore therein to the action of Athe steam and air, the sulfur given off bythe ore mixing with the hydrogen of the gases and passing off throughthe stack. The unconsumed oxygen being absorbed by the ore causes thelatter to be converted or transformed from refractory ore to oxidized orfree-milling ore, as will be readily understood.

In practice the speed of revolution is such that it requires about fortyminutes to complete one revolution ofthe cylinder; but the speed ofrevolution and the time, usually from one to two hours, which the ore issubj ected to this treatment will depend, of course, on the quality ornature of the ores treated and the intensity of the heat generated, asWill be understood.

As the operation or manipulation of the various parts has been describedin detail, a recapitulation is believed to be unnecessary.

From the above description it Will be apparent that I have produced anapparatus for oxidizing refractory ores possessing the features ofadvantage enumerated as desirable in the statement of invention, and itis to be understood, of course, that While I have illustrated anddescribed the preferred embodiment of the invention I reserve the rightto make such changes in its detail construction, form, proportions, orarrangement of the parts as properly fall Within the spirit and scope ofthe claims.

Having thus described the invention, what I claim as new, and desire tosecure by Letters Patent, is f l. An apparatus of the characterdescribed, comprising a rotary ore -retaining cylinder having aneck-passage, and an exit-opening of smaller diameter than saidneck-passage, a furnace communicating with said neck-passage, a steampipe for discharging steam through the furnace and said neck-passageinto said cylinder, and means for discharging steam and air into saidneck-passage at an angle to the rst-named steam-pipe,'substan tially asdescribed.

2. An apparatus of the character described, comprising a rotaryore-retaining cylinder having a neck-passage, and an exit-opening ofsmaller diameter than said neck-passage, a furnace communicating Withsaid neck-passage, a steampipe for discharging steam through the furnaceand said neck-passage into said cylinder, a chamber encircling andadapted to discharge steam and air under pressure into saidneck-passage, and valves for regulating and controlling the supply ofsteam and air to said chamber, substantially as described.

3. An apparatus of the character described, comprising a rotaryore-retaining cylinder having a neck-passage communicating with itsfront end, and an exit-opening of smaller diameter than saidneck-passage, a furnace communicating with said neck-passage, asteam-pipe for discharging steam through the furnace and saidneck-passage into said cylinder, means for discharging steam and airinto said neck-passage at an angle to the firstnamed steam-pipe, and anair-blastarranged to discharge into the furnace, substantially as andfor the purpose described.

4. In an apparatus of the character de-' scribed, a rotary ore-retainingcylinder hav- Y ing a neck-passage and an exit-opening, a furnacecommunicating With said neck-passage, means for discharging steam andair into the furnace, a door closing the rear end of the cylinder, andprovided with an exitopening, a stack 'connected to said exit-opening,and means for disconnecting said stack from said exit-opening in orderthat the door may be opened, substantially as and for the purpose setforth.

5. In an apparatus of the character described, a rotary ore-retainingcylinder having a neck-passage and an exit-opening, a furnacecommunicating With said neck-passage, means for discharging steam andair into the furnace, a door closing the rear end of the cylinder, andprovided with an exitopening, a movable stack, and a sliding sleevecarried by said stack and connecting the same With said exit-opening,substantially as described.

6. In an apparatus of the character described, a rotary ore-retainingcylinder having a neck-passage and an exit-opening, a furnacecommunicating with said neck-passage, meaus for discharging steam andair IIO IIS

into the furnace, a door closing the rear end of' the cylinder, andprovided with an exitopening and a surrounding neck, a stack comprisinga vertical stationary portion and a movable portion, a pipetelescopically connecting the movable portion to the stationary portionand a pipe telescopically connecting the movable portion and saideXit-opening neck, substantially as described.

7. In an apparatus of the character described, a rotary ore-retainingcylinder having a neck-passage, a furnace communicating with saidneck-passage, means for discharging steam and air into the neck-passage,a door closing the rear end of the cylinder and provided with an exitopening and a sur# rounding neck, a stationary track, and a stackconsisting of a movable portion provided with wheels resting upon thesaid track and a stationary portion, the movable portion having pipestelescopically connected to the stationary portion and to the neck ofthe exitopen`- a

